The grid revolution: Superconductors powering a safe, efficient energy transition

As demand from electric vehicles, hydrogen production, and heating and cooling systems accelerates, grids face unprecedented pressure. However, much of today’s cable network—particularly in Western Europe, North America, and Japan—is already decades old, never designed for the loads we are seeing today.

Take, for example, a distribution system operator in New York with a cable network that’s over 50 years old and operating near capacity. Adding new loads from EVs and heat pumps not only accelerates the aging of existing cables but also limits the ability to connect new renewable generation due to thermal and voltage constraints. Replacing or upgrading these cables using conventional high-voltage solutions requires extensive excavation in urban areas, where underground space is already crowded with telecommunications, water, gas, and transport infrastructure.

Even when installation is technically possible, environmental restrictions, lane rental charges, and traffic management fees can increase project costs by hundreds of thousands of dollars. Land acquisition for wider cable routes compounds the challenge, particularly when existing rights-of-way cannot accommodate the spacing needed for conventional cables, which require significant separation to manage heating effects and electromagnetic interference.

Meanwhile, safety and reliability requirements keep rising. Networks must deliver electricity without cuts, breakdowns, cascading failures, or blackouts. They need to handle fault currents that can damage critical assets like transformers and switchgear. And as public expectations grow, networks must minimize electromagnetic interference, reduce CO₂ emissions, recycle obsolete assets responsibly, and reassure communities about safety.

This scenario is playing out in major cities worldwide, while rural areas face their own infrastructure constraints. Meeting electrification needs at scale will require massive infrastructure upgrades: grids will need roughly 80 million kilometers of new or refurbished cable by 2040 – and conventional systems alone cannot keep up with demand.

High-Temperature Superconducting (HTS) cables and fault current limiters represent a fundamentally different approach to power transmission. The technology exploits the complete loss of electrical resistance that occurs in certain materials at extremely low temperatures, known as one of the key properties of superconductivity.

HTS materials require cooling to approximately -200°C, typically with liquid nitrogen. “High temperature” here means relative to the first generation of superconductors, which requires temperatures below -243°C to operate. The liquid nitrogen circulates in cryogenic envelopes, a thermally-insulated jacket that surrounds the cable. Liquid nitrogen is relatively inexpensive, environmentally harmless, and easier to manage than many industrial coolants. More importantly, the energy saved by eliminating transmission losses exceeds the energy required to maintain the cryogenic environment.

The electricity flowing through your home right now has traveled hundreds of miles of conventional resistive cables, losing roughly 10% of its power along the way. That waste, about 180 TWh annually in Europe alone, is enough to power three major cities. HTS cables requires 10 times less energy to supply electricity.

Why choose superconducting cables?

For modern grids, HTS systems offer huge advantages over conventional alternatives, especially in dense urban environments:

• Space efficiency and economics: HTS cables generate no heat or electromagnetic fields at any load along the cable route, so phases need no separation. Cables can be buried at any depth and close to other multi-energy network without expensive tunneling or specialized conduits, shrinking rights-of-way to up to one-tenth the width of conventional systems. In cities where land costs tens of thousands per meter, this benefit alone is game-changing.
• Enormous transmission capacity: One HTS cable can handle over 3 gigawatts. Fewer circuits and minimal substation upgrades are needed, while retrofits can multiply tunnel capacity without major construction with minimal electrical loss if not zero in Direct Current.
• Smaller environmental footprint: Less excavation and reduced permitting complexity can result in shorter project timelines and less public opposition.
• Resilience: Fully shielded, superconducting cables are weatherproof, highly secure, and nearly free of stray electromagnetic fields – meaning power availability is protected even if part of the grid is disrupted.

It’s a win-win(-win-win).

• Any source, anywhere: HTS cables handle rooftop solar, fuel cells, remote wind parks.
• Automatic protection: SFCLs limit fault currents instantly, no active controls needed.
• Smart, resilient grids: SFCLs allow the increase of supply and demand, improving reliability and supporting integration of distributed or remote generation.
• Electrification ready: Scales EV charging and industrial loads without massive new builds.

Ready for a superconducting grid revolution?

Infrastructure demands, technological maturity, and a strong business case are aligning to support widespread HTS adoption. Companies like Nexans, with facilities across Germany, France, and Norway, have developed cutting-edge expertise across the entire superconducting technology stack and are contributing to international standards that will accelerate global rollout.

The question isn’t whether superconducting technology will transform electrical grids, but how quickly utilities, governments, and investors will recognize the opportunity. Grid operators who move early will gain significant competitive advantages in efficiency, reliability, and capacity. Those who wait may find themselves constrained by the very infrastructure limitations that superconducting technology is designed to solve.